BSRG PG Fieldtrip: Skye, Scotland (2005)

A series of superb sections with well exposed Mesozoic sediments will be examined on Skye. The sediments were deposited in actively subsiding half-grabens and record brackish and shallow marine/deltaic environments with significant variations between wave and tidal-influence. The fieldtrip will focus on 1) interpretation of tidal and wave influence within shallow marine and brackish siliciclastic sediments and 2) illustration and discussion of published sequence stratigraphic interpretations.

From a petroleum geology viewpoint, at virtually all the localities it is possible to look at aspects of heterogeneity which are likely to affect fluid flow, particularly vertical and horizontal variations. At a larger scale (between outcrops) it is possible to infer variations in reservoir architecture-heterogeneity related to changes in base-level (i.e. incised valley fills cutting shoreface). In addition it is possible to illustrate changes in architecture-heterogeneity between the same stratigraphic units in different sub-basins. In other words, despite potential reservoir units being the same age, the architecture/heterogeneity and likely mechanisms of production from these reservoirs is completely different as you cross a fault. In most localities it is also possible to see the development of small-scale faults (discussion of sealing/non-sealing capacity) and the effects of igneous intrusions on cementation and fracturing of sandstones, and maturation of organic-rich mudstones.